Electrochemical CO2 reduction represents a sustainable approach for the conversion of CO2 into valuable fuels and chemicals. Here, we fabricated a series of composite nanomaterials through template-oriented polymerization of covalent organic frameworks (COFs) with isolated cobalt porphyrin units on amino-functionalized carbon nanotubes for efficient electrocatalytic CO2 reduction reaction (CO2RR). Compared with pure COFs, the hybrid form of ultrathin COF nanolayers wrapped on the conductive scaffold leads to distended current density and stable Faradaic efficiency for CO2-to-CO conversion over a wide potential range. Specifically, the catalytic performances of the system can be finely optimized by the modification of the reticular structure with different functional groups. Our work gives a new strategy for the preparation of highly active and selective electrocatalysts for CO2RR.The ever-increasing reliance on nonrenewable fossil fuels due to massive urbanization and industrialization created problems such as depletion of the primary feedstock and raised the atmospheric CO2 levels causing global warming. A smart and promising approach is artificial photosynthesis that photocatalytically valorizes CO2 into high-value chemicals. The inexpensive layered semiconductors like g-C3N4 and rGO or GO have the potential to make the process practically feasible for real applications. The suitable band positions with respect to the reduction potentials coupled with the typical surface properties of these layered semiconductors play a beneficial role in photoreduction of CO2. Additionally, the creation of heterojunction interfaces to achieve the Z-scheme by anchoring g-C3N4 and rGO with another semiconductor with proper band alignment and dispersing plasmonic nano metals to obtain Schottky barriers on the layered surfaces also help retarding the electron-hole recombination and boost up the catalytic efficacy. Extensive exploration happened in recent years toward artificial photosynthesis over these materials, which needs a critical compendium. Surprisingly, in spite of the recent explosion of studies on photocatalytic reduction of CO2 over metal-free semiconductors, there is not a single review on comparing the mechanistic aspects of photoreduction of CO2 over the layered semiconductors g-C3N4 and rGO. This review stands out as a unique documentation, where the mechanism of photocatalytic reduction of CO2 over this set of materials is critically examined in the context of band and surface modifications. An overall conclusion and outlook at the end indicates the need to develop prototypes for artificial photosynthesis with these well-studied semiconducting layered materials to yield solar fuels.Rational synthesis of bifunctional electrocatalysts with high performance and strong durability is highly demanded rechargeable metal-air battery. In this work, ZIF-derived Co9S8/C coated with conductive graphene nanosheet (Co9S8/GN) was synthesized by a simple solvothermal method and formed a stable double-carbon structure. As expected, the prepared Co9S8/GN catalyst exhibits a high catalytic activity (ΔE 0.88 V) and long-term durability toward both oxygen reduction reaction and oxygen evolution reaction (ORR and OER), which is even superior to the Pt/C + Ir/C mixture (0.91 V). In addition, the Zn-air battery with the Co9S8/GN catalyst showed higher power density (186 mW cm-2) and more stable charge-discharge cycling performances (2000 cycles) than the Pt/C + Ir/C (118 mW cm-2). Based on these analysis results, the favorable catalytic performance of ORR/OER should be illustrated by the following reasons (i) large specific surface area and unique mesoporous structure, providing abundant active sites; (ii) good conductivity, accelerating the electrons transfer; and (iii) the unique stable "double-carbon" structures (metal-S-C-C), preventing the agglomeration of metal sulfide, building new quick transfer pathway, and forming the strong electron coupling ability and synergistic effect.CuInP2S6 (CIPS) is a van der Waals material that has attracted attention because of its unusual properties. Recently, a combination of density functional theory (DFT) calculations and piezoresponse force microscopy (PFM) showed that CIPS is a uniaxial quadruple-well ferrielectric featuring two polar phases and a total of four polarization states that can be controlled by external strain. Here, we combine DFT and PFM to investigate the stress-dependent piezoelectric properties of CIPS, which have so far remained unexplored. The two different polarization phases are predicted to differ in their mechanical properties and the stress sensitivity of their piezoelectric constants. This knowledge is applied to the interpretation of ferroelectric domain images, which enables investigation of local strain and stress distributions. The interplay of theory and experiment produces polarization maps and layer spacings which we compare to macroscopic X-ray measurements. https://www.selleckchem.com/products/cetirizine.html We found that the sample contains only the low-polarization phase and that domains of one polarization orientation are strained, whereas domains of the opposite polarization direction are fully relaxed. The described nanoscale imaging methodology is applicable to any material for which the relationship between electromechanical and mechanical characteristics is known, providing insight on structural, mechanical, and electromechanical properties down to ?10 nm length scales.The time evolution of three-dimensional (3D) printed food structures as affected by their composition and postprinting stimulus is an area of research that has recently received increasing attention. In this study, the spontaneous shape change of 3D printed purple sweet potato purees of different formulations as triggered by microwave dehydration was investigated. The rheological properties, water distribution behavior, and dielectric properties of the purees were first studied. Addition of salt reduced the viscosity, storage modulus, loss modulus, and yield stress but increased the relaxation time of the purees. Addition of fructose syrup resulted in opposite results. Addition of both salt and syrup decreased the dielectric constant but increased the dielectric loss of the purees. Increased microwave power and salt content increased the rates of dehydration and deformation but decreased the maximum deformation degree of the printed samples. The syrup also decreased the maximum deformation degree. A desirable deformation pattern could also be achieved by manipulating the infill parameters.